Grater



1941- .1. A. MURDOCK 7 2,252,859

GRATER Filed July 17, 1939 @1 9 Patented Aug. 19, 1941 ,UITED STATES PATENT OFFICE GRATER James A. Murdock, Chicago, Ill. Application July 17, 1939, Serial No. 284,874

3 Claims.

This invention relates to an improved grater. An object of the invention is to provide a grater which may be easily and economically manufactured and assembled.

A further object of the invention is to provide a grater which may be used without danger to the user and which may be easily cleaned of the particles which cling to a grater after use.

A further-object of the invention is to provide a grater with cutter bars of unique design, so formed as to permit grating of soap, food and other objects into extremely fine particles or fairly coarse particles at the users option merely by varying the pressure applied to the article to be grated.

Another object of my invention is to provide a grater with cutter bars so formed and so placed with respect to the perforations through the grater body that the grater is practically selfcleaning and the cutter bars are never clogged with accumulated gratings.

Further objects, advantages and capabilities of the invention will appear from the following description of a preferred embodiment thereof, taken in conjunction with the accompanying drawing, in which:

Figure 1 is a plan view of the entire grater;

Fig. 2 is a section of the grater body taken on the line 2-2 of Fig. 1;

Fig. 3 is a sectional detail view of a fragment,

of the grater body taken on the line 3-3 of Fig. 1;

Fig. 4 is a perspective view of a fragment of the grater body showing the arrangement of the cutter bars and their location with respect to the perforations in the grater body;

Fig. 5 is a transverse section of a single cutter bar taken on the line 5-5 of Fig. 3; and

Figs. 6 and 7 are transverse sections of alternative forms of cutter bars.

Referring to the drawing, the grater is mounted upon a frame H which may take various forms, but which I have shown in the form of a rectangular Wire frame formed into a handle l2 at one end of the grater and into two legs l3 at the other end of the grater. Attached to the frame H is the grater body M which I have shown in the form of a stamped metal plate with the side edges and a number of flanges l5 at both ends of the grater body turned about the frame H to secure the grater body to the frame. Although I have shown the grater body I in the form of a stamped steel plate, it may be conveniently made in other forms and from other materials, such, for example, as a die cast metal plate or a molded plastic plate, or, if desired, the body and handle may be die cast or formed as a single unit.

The grater body It is formed into a rectangular frame portion composed of the four margins of the grater body surrounding a web which forms the grater member of the assembly. The web is composed of the longitudinal ribs [6 and the transverse cutter bars I? which are all integrally formed with the frame portion of the grater body, although these may be formed separately and secured to the grater frame. The longitudinal ribs 16 and cutter bars I! enclose a series of rectangular perforations l8 through the grater body l4, forming a web with the area of the perforations in excess of the area of the solid portions of the grater. These details of structure are best shown in the detail View, Fig. 4.

The longitudinal ribs [6 may be formed in the same plane as the frame portion of the grater body l4, although if the grater is stamped from sheet metal the formation of the transverse cutter bars I7, which will be presently described, will twist the longitudinal ribs slightly out of the horizontal plane, as shown in Fig. 3. The transverse cutter bars I! are substantially rectangular in section, as shown in Fig. 5, but are bent throughout their length in inclined planes alternately descending below and rising above the plane of the frame portion of the grater body. This is best shown in Fig. 3 and in the perspective view Fig. 4 of the drawing.

It is also preferable that alternate cutter bars be inclined in the same direction, and in the opposite direction from the adjacent cutter bars,

as shown in Fig. 3.

While I have shown the cutter bars bent into flattened S-shaped portions between adjacent rectangular ribs, as seen in Fig. 3, the shape of these portions can be varied as long as portions of the cutter bars protrude above the plane of the longitudinal ribs and, if both sides of the grater are designed for use, also below the plane of the longitudinal ribs.

As shown in Fig. 5, the transverse cutter bars are formed with edges l9 which form the cutting edges of the cutter bars. An essential feature of my invention is that the cutter bars have substantial faces 20; which, because of the conformation of the cutter bars, protrude above the plane of the longitudinal ribs and form walls to the rear of the perforations l8, and are thus presented directly to the object to be out.

In the alternative forms of cutter bars shown a in section in Figs. 6 and '7 the respective faces 22 and 24 are shown slightly inclined from the vertical, giving a slightly different formation to the respective cutting edges 2| and 23.

The operation of the grater heretofore described is as follows:

The grater is held in one hand by the handle 12 with the legs 13 against a firm surface, such as a table. The grater body may be held Vertically, horizontally or at an inclination with respect to the table. The object to be grated is held in the other hand, forced against the face of the grater body with light pressure, and moved either longitudinally along the grater or at some angle to the transverse cutter bars other than directly parallel with them. Slight pressure upon the object being grated forces the protruding portions of the cutter bar into the object so that as the object is moved against the grater the cutting edges |9 chip off portions of the object.

, Because of the substantial faces 20 upon the front of each cutter bar the cutter bars do not enter into the object to shred it into long shavings, but merely chip off short chips which readily pass throughjthe openings H8 in the body of the/grater and clear the grater for succeeding chips; The extensive area of the perforations insures that the gratings will immediately and completely be cleared from the cutter bars.

By varying the pressure of the objects upon the grater body the fineness of the grating can be readilycontrolled. By varying the shape of the cutter bars, as shown in the alternative forms,

Figs. 6 and '7, the fineness of the grating can also hevaried. Where the face 22 of the cutter bar 21 is at an obtuse angle to the upper surface of the cutter bar, as shown in Fig; 6, a finer chip will be produced, and if the cutting edge 23 is undercut, as shown in Fig. '7, a coarser chip will be produced.

The arrangement'of the cutter bars about the grater body it, with the cutting edges 19 directly'ov er the limits of the openings 18 and without any of the grater bodybelow the cutting edges 19, makes it impossible for'the gratings to accumulate and clog the grater. The grater is thus practically self-cleaning. Because of the lack of .anycrev'ices or pockets for the accumulation of chips the grater can be readily cleaned by passing it through water. 7

Where the grater is made in the preferred form shown in the drawing, Figs. 1, 2, 3 and 4, both sides are equally available for use and equally effective in grating action. If desired, the extent of the projection of the cutter bars I! below the plane of one surface of the frame portions of the grater can be made greater or less than the projection of the cutter bars above the plane of the other surface of the grater and thus the depth of cutting action of one side of the grater can be varied from that of the other side. In either case, the method of operation of the grater is identical.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A grater comprising a frame, said frame having a handle member and legs, a plate having solid margins secured to said frame, perforations in said plate, within said margins and walls about said perforations, said walls being substantially vertical to the plane of said plate and having portions thereof projecting beyond the plane of said plate.

2. A grater comprising a plate, frame portions about the margins of said plate, longitudinal ribs joining opposite frame portions of said plate, transverse cutter bars connecting said longitudinal ribs, portions of said cutter bars being deformedout of the plane of said longitudinal ribs and having two faces in planes substantially perpendicular to the plane of said ribs.

3. A grater comprising a flat plate having around its periphery a rigid frame portion and being formed in its central portion with elongated spaced ribs supported at their opposite ends by said frame portion, and elongated cutter bars merging into and intersecting said ribs at angles thereto and coplanar with the ribs at the intersections and formed intermediate the ribs with portions projecting beyond the plane of the plate, each of said portions being formed on at least one side with a plane face lying at substantially a right angle to the plane of the plate.

JAMES A. MURDOCK. 

